package org.alanlau.ribbon.interceptor;

import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
import org.springframework.cloud.client.loadbalancer.LoadBalancerRequestFactory;
import org.springframework.http.HttpRequest;
import org.springframework.http.client.ClientHttpRequestExecution;
import org.springframework.http.client.ClientHttpRequestInterceptor;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.util.Assert;

import java.io.IOException;
import java.net.URI;

/**
 * 自定义负载均衡拦截器
 *
 * @author alan
 * @version 1.0
 * @date 2020/9/13 19:09
 */
public class MyLoadBalanceInterceptor implements ClientHttpRequestInterceptor {
    private LoadBalancerClient loadBalancerClient;
    private LoadBalancerRequestFactory requestFactory;

    public MyLoadBalanceInterceptor(LoadBalancerClient loadBalancerClient, LoadBalancerRequestFactory requestFactory) {
        this.loadBalancerClient = loadBalancerClient;
        this.requestFactory = requestFactory;
    }

    public MyLoadBalanceInterceptor(LoadBalancerClient loadBalancerClient) {
        this(loadBalancerClient, new LoadBalancerRequestFactory(loadBalancerClient));
    }

    @Override
    public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
        final URI originalUri = request.getURI();
        String serviceName = originalUri.getHost();
        System.out.println("进入自定义的请求拦截器中" + serviceName);
        Assert.state(serviceName != null, "Request URI does not contain a valid hostname: " + originalUri);
        return this.loadBalancerClient.execute(serviceName, requestFactory.createRequest(request, body, execution));
    }
}
